Let me give you small advice considering Elafonisi visit. It will be very nice if you prepare enough food and drinks because I didn’t find any restaurant near the beach.
How can I get to the Elafonisi beach?
From Iraklion (the capital of the Crete) you can get to the Elafonisi by E75 road, which becomes E65 at the western part of the road. Near Kastellion village you can turn left inland and continue your move forward.
If you miss the turn, please, don’t worry in this case you will move along the south shore of Crete. It will take a little more time but at the end you will reach Elafonisi.
Be cautious because both ways are mountain roads and don't digress often to the spectacular views of the Crete.
During the summer season there is bus connection between Elafonisi and Chania (big city at the west part of the Crete). Also you can just buy excursion near your hotel to the Elafonisi. It may be the simplest way to reach the beach but be ready that tour bus could be overcrowded.